The article is devoted to the current state and analysis of factors affecting the use of alternative energy sources on a global scale. There is a constant growth in volumes energy consumption, which is associated with the stability of the global economy, increasing costs for heating and cooling in various parts of the world. At the same time in the most densely populated areas (China, India), coal accounts for up to 80 % of the energy balance, which leads to an increase in CO2 emissions. In this regard, the article notes the need to switch to the use of alternative energy sources (wind, solar, hydro, geothermal and biomass, nuclear energy). The article analysis the current state of energy sources in developed countries according to statistics for 2018. The authors concludes that the growth rate of renewable energy resources is insufficient, despite their advantage over traditional sources. In this regard, the factors affecting the efficiency of renewable energy sources were summarized. In addition, the article identifies barriers that prevent the acceleration of the rate of replacing traditional energy sources with RES. At the same time, state support measures and relevant legislative acts play a special role in stimulating and attracting the necessary investments.